Leather-stretching machine.



m0. www. Patented Feb. l2, |9ol.

F. H. cnoul..

LEATHER STBETGHINE MACHINE. (Appncasion med spt.' 25.. i599.) (No-Modaal.) 3 Shgets-Sheet I.

l 'Imp' 'In' Laren/fo 71 w www@ y WW - Patented Feb. I2, |90I. F. H. CBUUL. LEATHER STRETCHING MACHINE. (Application glad s'eps. 25, 1399.) (Mn ummm.)v a sheets-shear 2.

ING. @68,031 Patentd Feb. l2, |90I. F. H. GROUL.

LEATHER STBETCHING MAGHINE. (Application led'Sept. 25, 1899.) (mn modem a sham-sheet s.

w f y 597 @UWM/f @Tafllt Partnr @trice FRANK II. CROUL, OF DETROIT, MICHIGAN.

hEA'IHEHnSTHETl-HNG h/liCl-IINE.

srncrrcarrnn" forming ps1-t of Letters Patent No. 668,037, dated February 12, 1901.

Application filed September 25, 1899. Serial No. 731,627. (No model.)

.To @ZZ wiz/0m it lim/jl; concern;

Be it known that I, FRANK I-I. CROUL, a citi- Zen of the United States, residing at Detroit, in the county oi' llTayne and State of Michigan, have invented certain new and useful Improvements in Ileather Stretching Ma chines, of which the following is a specification, reference being had therein to the accomganying drawings.

rI`he invention consists in the construction of a leather-stretching machine, and particularly in the construction of the scraper device whereby it may be readily adjusted to different classes of work and whereby it produces a more inished surface upon the scraped leather than machines heretofore used.

lhe invention further consists in the construction, arrangement, and combination of the various parts, as more fully hereinafter described, and specifically pointed out in the claims.

In the drawings, Figure l is a side elevation of my improved machine. Fig. 2 isa top plan view thereof, partly in section. Fig. 3 is alongitudinal section through the machine. Fig. fi is an end elevation. Fig. 5 is a perspective view oi' one end-of the scraper frame or bed, showing one of the Scrapers in sectional perspective. Fig. is an enlarged section through one ot the Scrapers, and Fig. 7 isa detached elevation oil the parts comprising the scraper and its support.

A represents a suitable frame in Which the operating parts are supported. Stationarily supported upon the top of the frame is a clamp B, which is adapted to grasp one end of the hide or piece of leather to be stretched. l@ is a complementaryclamp for the other end ci the hide or piece of leather,and this is supported upon the beam D, which is supported in suitable guides in the frame of the machine. llhe clamp 1U is adapted to be moved to and from the clamp B by any suitable means. I have shown the beamD provided with a rack-bar E and a train of gears F, one of which meshes with the rack bar and another of which is provided with a suitable crank G for operating the same.

@n the frame of the machine are suitable guides in which slides the scraper frame or table II, which is shown in Fig. 5 in detail.

This frame or table operates between the pairs of clamps referred to and carries a series ot' scrapingr bars or blades which are adapted to stretch the hide or leather While under tension while being held in the clamps. These scraper-blades I preferably make as `follows: Upon the table or bed II, I secure a series ot' vertical flanges I, arranged in pairs a suitable distance apart and spaced between each pair, forming agroove orsocketin which the ribs or fins .I are supported. They are vertically adjustable by any suitable meanssuch, for instance, as by the clamp-screws K. (Shown in Figs. 5 and 6.) Upon the top of each rib or standard J is a cap L, preferably bifurcated, as shown, so as to slide down and iit upon the top of the standard J, as plainly shown in Fig. (i. Between the top ofthe standard and the under `face of the cap l preferably arrange a spring, usually in the nature of a piece or block of rubber, as shown. at M in Fig. 6, this rubber being sufficiently hard to slightly yield when the pressure becomes too great in use. The scraping-face I preferably form, as shown in the drawings, by the two bevel-faces a upon opposite sides and the flat face b upon the top, forming the obtuse-angled scraping edge c. But one of these angled scrapingiaces is in use on each scraper blade or cap; but by making a pair of these scraper-faces with this construction I am enabled to reverse the cap when one angle of the cap has worn oit and use the other. These caps I preferably make of brass, as I indI get the best resultin working the leather with such a cap. I also find that an angled face for scraping gives me a better result than a rounded face, and an obtuse angle is better than an acute, because an acute angle is apt to cut the hide off it' proper tension is put upon it in stretching. A series ot' these scraping-blades thus constructed I arrange side by side,with their upper faces in a curved line which is usually substantially the arc of a circle, as plainly shown in Fig. l, rising above the plane upon which the hide is clamped at the ends. By arranging them this way I am able to lget the independent scraping action of each blade separately upon the under face of the hide, and its angled face will not only scrape and stretch the hide, but

IOO

will slightly bend and work it, as will be readily understood from an inspection of the drawings.

The scraper-frame is reciprocated in any suitable manner; but I prefer to employ the following devices: O represents rock-arms jonrnaled upon the studs O in the sides of the frame and extending at their upper ends beside the scraper-frame. On the scraperframe are wrist-pins P, engaging in an elongated bearing P in the upper end of the rockarms. Q is the crank-shaft, driven from any suitable source of power and having connecting-rods R connected to the rock-arms O intermediate their ends.y This connection is made in the slot S and is adjustable therein, so as to vary the length of stroke of the arms.

The parts being vthus constructed and arranged, their operation is as follows: The operator clamps one end of the hide in the clamp B and the other end of the hide in the clamp C. The adjustable clampis then moved away from the stationary clamp by the turning of the crank G until suitable tension is .put upon the hide, which is thus stretched over the scraper-bars, as shown in Fig. 3. The operator sets the machine in motion and reciprocates the scraper-blades beneath the hide, scraping the under side thereof and stretching it, and after the first stretching takes place the movable clamp is adjusted farther away and stretching resumed until the hide is stretched substantially to its elastic limit, when it is removed from the machine and a new one inserted in its place.

It willbe observed that my scraping is done by an angle or edge c on the scraper which projects into the plane of the hide stretched thereover and is formed by arranging the two faces of the scraper which form the angle c so that they will stand at an acute angle to the plane of the surface of the hide to be scraped.

What I claim as my invention isl. In aleather-stretching machine,tlie combination of a bed, arigid scraper-frame thereon, a series of scraper-blades supported thereon a spring-backing for each blade and means for moving the Scrapers in relation to the clamped hide.

2. In aleather-stretching machine,the combination of the leather-clamps, a series of scraper-blades between, and means for effecting a relative movement between the clamped leather and blades, guides in which the scraper-blades are adjustably supported and means for holding the blades in their adjusted positions.

3. In aleather-stretching machine,the combination of the leather-clamps,ascraper-frame between, means for effecting a relative movement between the frame and clamped leather and scraper-blades on the frame comprising a series of standards on the frame, and detachable scraping-caps on the standards, said caps having an obtuse-angled outer scraping edge.

4. In aleather-stretching machine,the combin ation of theleather-clamps,a scraper-frame between, means for effecting a relative movement between the frame and clamped leather, and scraper-blades on the frame, comprising a series of vertically-adjustable standards on the frame, and detachable scraping-caps on the standards, having obtuse-angled scraping edges.

5. In a leather-stretching machine,a scraperframe, a series of rib-like standards thereon, vertically adjustable, a bifurcated cap slidingly engaging over the top of each standard, and a spring between the cap and standard.

6. In a leather-stretching machine, means for holding the hide, and a scraper device over which the hide is held, comprising rigid scraper-blades havingascraping edge formed by two faces of the blade which extend at an acute angle in relation to the plane of the stretched hide.

7. In a leather-stretching machine, means for holding the hide, a movable scraper device comprising supports and detachable reversible scraper-caps thereon, substantially as described.

8. In a leather-stretching machine, means 4 for holding the hide, a movable scraper device comprising supports, and detachable,reversi ble caps, having on both sides angled scraping edges, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

FRANK I-I. CROUL. Witnesses:

JAMES WrirmnMoI-in,A M. B. ODOGHERTY. 

